There is almost nothing more comforting than when a cat jumps on our lap and begins to purr. Ever since the Egyptians started worshiping the cat, philosophers, scientists and cat lovers worldwide have wondered why cats purr. When we hear and feel this purring, we assume that everything is just fine with the cat. But why do cats purr? And what produces this sound?
Purring is still somewhat of a mystery; however, most experts agree that it’s due to the vibration of the vocal cords when the animal inhales and exhales.
It appears as though purring is not just limited to domestic cats. Some wild cats, such as pumas and mountain lions, are able to purr. In general, most large cats that cannot roar are able to purr. The calls of the leopard vary and include a series of harsh coughs, throaty growls, and deep, purring sounds.
It turns out that cats have special wiring traveling from the brain to the muscles in the vocal cords. Nerve signals that pass through this wiring system cause vibrations of the vocal cords. While the nerves cause the vocal cords to vibrate, the air forced through them by the diaphragm causes the musical hum. Since breathing has both inspiratory and expiratory phases, cats purr continuously.
It is commonly believed that cats purr when content. However, cats also purr when they are severely injured, frightened or giving birth. According to some veterinarians, the original function of the purr was to enable a kitten to communicate with his mother that things are going well. A kitten is able to purr by the second day of life, and although he can’t meow and nurse at the same time, he can purr and nurse.
As the cat matures, the meaning of the purr changes. Some cats purr to indicate contentment or pleasure, but badly frightened cats and severely ill cats also purr. It is not uncommon for cats to purr when they are close to death. This final purring may indicate a state of anxiety or possibly euphoria. These states have also been elucidated in terminally ill people.
Since the purr has lasted through hundreds of generations of cats, there must be a survival mechanism behind its continued existence. Researchers believe that self-healing is the survival mechanism behind the purr. There is extensive documentation that suggests that low frequencies, at low intensity, are therapeutic. These frequencies can aid bone growth, fracture healing, pain relief, tendon and muscle strength and repair, joint mobility, the reduction of swelling, and the relief of dyspnea, or breathlessness. Purring may be linked to the strengthening and repairing of bones, relief of pain, and wound healing.
Animal behaviorists believe that when cats purr under stressful circumstances, they are reassuring or comforting themselves, much as humans may sing to themselves or hum when they are nervous. Frightened cats may purr to communicate submissiveness or non-aggressive intentions. A feral cat may purr to signal that he is not planning to attack and other cats need not feel threatened. Older cats may purr when they play or approach other cats, signaling that they are friendly and want to come closer.
If you have questions about your cat’s behavior or health, please don’t hesitate to call Long Island City Veterinary Center. Our goal is to help you and your pet in sickness and in good health.